DESCRIPTION: (Adapted from applicants abstract) Approaches to preventing or ameliorating psychosocial adjustment problems in adults who have completed treatment for cancer are limited both in quantity and methodologic rigor. When psychosocial interventions have been tested with cancer patients, they frequently combine multiple approaches in one intervention, and include subjects heterogeneous with respect to cancer diagnoses, treatment status, stage of disease, time since diagnosis, and prognosis. In addition, although descriptive studies with cancer patients and theories of social support suggest that including a significant other in an intervention will facilitate adjustment, there has been no investigation of the effect on subsequent psychosocial adjustment of the patient when interventions are targeted at both the patient and a family member rather than the patient alone. The purpose of this pilot study is to test the effect of a theoretically-based intervention (provision of concrete objective information) on the psychosocial adjustment of breast and prostate cancer patients following the completion of radiation therapy (RT). The study will compare the value of delivering the intervention to the patient alone or to the patient and a family member and will include a usual care comparison group. The sample will consist of 36 women with breast cancer and 36 men with prostate cancer randomly assigned to group. Positive and negative affect, cognitive disruption, social support, and perception of relationships will be measured at baseline and at the final 13-month follow- up. Psychosocial adjustment (affect and cognitive disruption) will be measured at each follow-up (1 week, 4-6 weeks, 4 months, 7 months, 13 months). Since psychosocial adjustment may vary with side effects, a measure of side effect severity will be taken at each data colletion point to serve as a covarite in the analysis of psychosocial outcomes. Specific hypotheses about the effects of interventions and subsequent tests of mediating effects will be conducted using repeated measures ANCOVA and hierarchical ANCOVA analyses.